Sewing machine



36-. J.GOULDBOURNML 2,055 221 SEWING MACHINE ori inal Filed Sept. 7, 1953 s Sheets-Sheet 1 1936- J. GOULDIBOURN ET AL SEWING MACHINE Original Filed Sept. 7, 1953 S-Sheets-Sheet 2 I XW " @hy/ozw 7 attorney NOV. 3, 1936. J B UR ET L 2,059,227

SEWING MACHINE Original Filed Sept. 7-, 1955 s Sheets-Sheet s V LI/I/(IAI'! W/IIIIIIIIIIII 'IIII' [I'll/1111111111111 (Ittorneg 54 5 60 mentor 2 W Patented Nov. 3, 1936' UNITED STATES PATENT OFFICE SEWING MACHINE Original application September 7, 1933, Serial No. 688,480. Divided and this application April 25, 1935, Serial No. 18,129. In Great Britain Octo- 1'7 Claims.

This invention is concerned with improvements in or relating to sewing machines, and is particularly, but by no means exclusively concerned with sewing machines for operating on thick stubborn materials such as leather.

An illustrative machine of this kind is disclosed in United States Patent No. 1,169,909 granted to Fred Ashworth, February 1, 1916, and also in the present inventors co-pending application Serial No. 688,480, filed September '7, 1933, for Sewing machines, of which application the present application is a division.

Usual machines of this kind employ mechanism for actuating the sewing instrumentalities which, while satisfactory for enabling the machine to sew efficiently, up to a speed of say five hundred stitches per minute or thereabouts, is not suited for enabling the machine to run at a relatively high speed, for example, to sew a thousand stitches per minute. In arranging a sewing machine to run at a high speed, it is important that both the indivual speeds of movement of the sewing instrumentalities in relation to the machine cycle and their relative timing be settled with a high order of accuracy so that the absolute time taken by the various instrumentalities in carrying out their individual functions may be made as small as is consistent with smoothness of operation and in order that they may cooperate one with another in complete harmony.

The objects of the invention are to provide novel forms of thread control devices cooperating with a take-up in furnishing the correct amount of thread for each stitch and securing effective setting of the latter (including in particular simple means rendering the customary auxiliary take-up unnecessary, a thread-measuring and pull-off mechanism operating with exceptional accuracy and an arrangement of alternately acting thread locks effectively guarding against loss of control of the thread by both locks).

In accordance with these and other objects, one feature of the invention contemplates the provision in an outsole shoe sewing machine having a. pull-off and thread locks of means connecting the thread looks so arranged that one look. is held closed whenever the other is opened. In order that the nature of the present invention may be more clearly understood, an illustrative embodiment including further features will now be described and the above objects of the invention and its. several features will become apparent to those skilled in the art from said description.

In the drawings: Figure 1 is a front view showing the head of the illustrative machine; Figure 2 is a view from the right hand side of the machine partly in section showing certain parts of thread measuring and thread locking means; Figure 3 is a View from the right hand side of the machine showing mechanism for actuating a thread measuring lever and for actuating dual thread locks of the machine; Figure 4 isa sectional view from the front of the machine showing certain details of thread locking means of the machine; Figure 5 is a view from the right hand side of the machine showing certain details of the parts seen in Figure 4, and Figure 6 is a detail sectional plan view showing parts of the mechanism for actuating the thread measuring lever.

The said illustrative embodiment of the invention is a machine designed for sewing the outsoles of weltedshoes to their welts and comprises a column I and a head casing 5. A main shaft Ill is arranged parallel to the front of the machine (i. e., from left to right) and has mounted on it cranks and various cam members which actuate needle, awl, and other mechanisms of the machine and the thread measuring means.

Geared to the main shaft I0 and rotatable in the machine frame are additional shafts l2 and M. The shaft I4 is surrounded by a hollow shaft or sleeve l6 rotatable around it and a driving connection for rotating the sleeve I6 continuously and for oscillating the shaft is provided between the shaft and sleeve by gears contained within a case portion [8 of the frame. The shaft l4 and sleeve l6 cooperate to form a driving arrangement for a continuously rotating thread take-up device 20, described more particularly in United States Patent No. 1,941,943 granted January 2, 1934, to Keall, et al. The sleeve [6 has secured to it a cam member 22 by which operative movements are imparted to a pair of thread locking devices 24 and 26.

The stitch-forming devices include a curved hook needle 28, a curved aw] 30, a looper 32, a shuttle, the take-up and a thread finger 33. The needle and awl are mounted to oscillate in a common plane about an axis 34-. Means for feeding the work step-by-step through the machine comprise a, horizontally swinging worksupporting table 35 and a correspondingly mounted presser-foot 36 illustrated in Figure 1.

The thread passing from the supply upwardly through the locking device 24 (Fig. 2) mounted on the right side of a plate 31 is carried over a guiding roll 38 secured to the plate, then under a roll ii] projecting from a swinging thread measuring lever 32 and thence over a guiding roll 44 also secured to the said plate 31. The thread then passes downwardly around the rotary thread take-up 2G and thence between two further stationary rolls 36, 38 secured to the plate 31, and up through the thread passage in the upper end of the looper 32. The lever 42 is pivoted upon a fixed shaft 59 (Figs. 2 and 3) and its rear end is connected by a link 52 to the upper ends of a double link the members of which are of the same length as the link 52. The lower ends of this double link are pivoted to a swinging bifurcated bracket 56, the limbs of which are spaced apart to embrace the double link 54 and are of the same length as the double link. The said bracket has secured at its rear end horizontal spindles 58 which are mounted in fixed bearings carried by the head casting. A red Si] is secured to the pivotal connection between the links 52 and and is connected to a bell crank lever (32 mounted on a rod 6 3 and provided with a roll which enters into a cam groove in a cam member 68 secured to the main shaft I0. The bifurcaied bracket 56 is swung downwardly about its supporting spin-dies 58 by connections more fully described in the parent application to a presserfoct actuating lever, the arrangement being such that the extent to which the bracket is moved is determined by the thickness of the work. Downward swinging movement of the bifurcated bracket 56 causes the pivotal connection with the double link 5 to move into a lower position and this in turn causes the path through which the pivotal connection between link 52 and the double link 5 3 is moved by the cam member 66 to assume a direction which has a smaller component of vertical movement and a larger component of horizontal movement. The thinner the work being operated on, the less will be the vertical movement imparted to link 52 and the less will be the rocking movement imparted to the thread measuring lever 32. Thus, the extent of the rocking movement of the thread measuring lever and therefore the length of thread pulled 01f from the supply for each stitch is directly proportional to the thickness of the work.

The two guiding rolls 38 and 44 and the roll .69 on the thread measuring lever of the present machine are spaced so far apart that the gaps between the sides of the roll 40 on the measuring lever and the near sides of the stationary rolls 38 and M are both approximately equal to' the radius of the rolls when the roll 40 is in its highest position at which time it is still in engagement with the thread and deflects it downwardly somewhat from a straight position. This arrangement of the spacing brings about the result that as the roll .6 descends between the stationary rolls the angle between the sides of the bight of thread passing over the rolls will gradually decrease. Thus, assuming, for example, the thread roll 40 on the thread measuring lever to have a given maximum throw, the amount of thread drawn off from the supply during the first quarter of this throw will be a certain amount, the amount of thread drawn off during the next quarter will be greater than that drawn off during the first quarter, the amount of thread drawn off during the movement of the roll through the third quarter of its throw will be greater than either of the amounts drawn off during the movements during the first and second quarters and the amount of thread drawn off by the movement of the roll during the last quarter will be greater than the amounts drawn off by the roll during its movement through any of the three previous quarters of its throw, such an arrangement tending to allow the setting of the stitch lock to take place in the best position within the work according to variations in the thickness of the work.

The thread locking devices, according to the principal feature of the present invention, are provided to cooperate with the thread measuring roll 40 to allow thread to be pulled off from the supply without at the same time pulling thread from the sewing instrumentalities and to allow the thread measured oil from the supply to be used up correctly in the machine cycle.

These locking arrangements comprise the two thread gripping devices Ed and 28 arranged, one between the thread supply and the thread measuring roll 40 and the other between the thread measuring roll and the sewing instrumentalities. The lower lock 24 is positioned at a level below and somewhat forwardly of the roll 33 on the vertical plate 31. The lower lock E l comprises a thread engaging block 63 supported by a small bent bracket 65 secured to the vertical plate 31. The block 63 has on its right face a rounded rib 61 which extends forwardly and rearwardiy of the machine and is received in a similarly shaped groove in the bracket 65 so that the block may rock about the axis of the rib to engage the thread evenly. A second thread-engaging block E38 cooperates with the thread-engaging block 63 to grip the thread and block 68 is formed on one end of a stem 16 which extends through the vertical plate 31 within a sleeve 12 which is rotatably mounted in a boss 14 formed on the plate 31, but is prevented from endwise movement therein. The stem 18 is held against rotation and has a quick-acting thread 15 thereon with which meshes a similar thread on the inside of the sleeve 12. An arm 16 is secured on one end of the sleeve 12 and is connected by a link 18 to the upper end of a floating lever 88 (Fig. 3) which is pivotally connected at 82 between its ends to the upper end of a curved arm 84 of a bell crank lever 86 mounted to rock about a horizontal pin 88 secured to the vertical plate 31. Another arm of the bell crank lever 86 has a cam roll 99 extending from its lower end which engages in a cam groove in a cam member secured to the rotary sleeve IS on the shaft hi.

The thread engaging faces of the thread engaging blocks 63, 63 are of substantial length so that very effective locking of the thread is obtained during the setting of the stitch.

The upper lock is formed by the thread looking device 26 which comprises a thread clamping shoe arranged to be urged downwardly against the roll 44 to clamp the thread. To this end the clamping shoe 26 is mounted on a pivot 92 on the forward end. of an arm 9 which is fast on a shaft 96 rotatable in the vertical plate 31, and on the other side of said plate the shaft has fast to it an arm 98 connected to a link Hill, the lower end of this link being pivotally connected to the rear end of the floating lever 80. A forwardly extending ear I02 of the machine frame (Fig. 1) has formed on it a boss having a bore in it in which a plunger 58 i is housed. The plunger I04 is urged upwardly by a spring I06 to bear against the end of the floating lever 80. The plunger lfi l tends to rock the floating lever 3!! about pivot 82 on the bell crank le- :ver 86 in a counterclockwise direction looked at from the right, and thus tends to swing the clamping shoe 26 down on to the thread passing over the roll 44 and also tends to rotate the threaded sleeve 12 associated with the lower thread lock to cause the thread-engaging block 68 to be moved towards the cooperating thread engaging block 63. One or the other of the two upper and lower thread locking devices locks the thread at all times and assuming the upper thread lock to be closed and the lower lock open, the mechanism operates at the correct time in the cycle of the machine to lower the pivot 82 on which the floating lever 80 is mounted, and owing to the fact that the rear end of the floating lever is supported in a stationary position by the spring pressed plunger I04 while the upper lock 26 is closed the lowering of the pivot 82 will cause the forward end of lever 80 to move downwardly quicker than the pivot itself moves. Some time before the pivot 82 is lowered as far as possible by its cam (e. g. when it has been lowered about half way) the downward movement of the forward end of the floating lever will have rocked the threaded sleeve 12 so far that the threadengaging block 68 of the lower thread lock will grip the thread against the cooperating stationary thread-engaging block 63. When this has occurred further downward movement of the forward end of the lever 80 is prevented and continued movement in a counter-clockwise direction of the pivot 82 will cause the floating lever 89 to pivot about the pivotal connection at its upper end with link 18 and thus the rear end of the floating lever will now move downwardly and cause the clamping shoe 26 to rise out of contact with the thread. During this downward movement of the floating lever 80, the plunger Hi4 will be moved downwardly compressing the spring behind it to maintain the lower lock closedupon the thread. When the bell crank lever 86 is. later swung in a clockwise direction by its cam 22, the floating lever 80 is constrained by the plunger to move in a counter-clockwise direction about the pivot at its upper end, thus lowering the clamping shoe 26 on to the thread roll 44. Immediately the downward movement of this clamping shoe is arrested by contact with the thread on the roll, the rear end of the lever 80 is held stationary and continued upward movement of lever 80 causes the lower thread-lock 24 to unclamp the thread. An auxiliary tension spring I08 (Fig. 1) is coupled to the short arm 16 secured to the threaded sleeve 12 and assists the spring pressed plunger M to maintain lower thread lock 24 in thread-clamping position until the thread is clamped by the upper look.

In order to ensure that the thread will be held under sufiicient tension for it to be laid unfailingly in the needle barb by the looper,

.a friction thread tension device is provided between the rotary take-up 20 and the looper. This auxiliary thread controlling device comprises a downwardly extending leaf spring H0 (Fig. 2) secured to the rear of an arm H2 arranged to swing about a pin H4 secured in the plate 31. On the upper end of the arm M2 the thread hook 33 is formed and is actuated by a link H6 and a cam operated lever H8. The spring operates as the said arm H2 moves rearwardly in laying the thread in the barb of the needle, to grip the thread yieldingly against a hub of arm 94 which carries the thread clamping shoe 2.6 of the upper thread lock and thereby to make sure that the thread which is, being laid in the needle barb by the looper is in tension between the looper and thread hook even if the rotary take-up is at the time paying out more thread than is needed.

The mechanism for releasing the thread from the thread locks comprises the arm 16 (Figs. 3 and 4) which is secured at its forward end on the left end of sleeve 12 associated with the lower lock. The rear end of arm 75 has fixed in it a pin I28 (Fig. 3) which passes through a slot formed in the upper end of a rod I22 which, at its lower end, is pivotally connected to an arm of a bell-crank lever I2 8 pivoted on a stud E26 fixed in the left side of ear I02 of the frame. V

The other arm of bell crank lever I24 has pivotally connected to it the end of a rod I28, which rod extends rearwardly and is connected to the driving and stopping mechanism of the machine. As the machine comes to rest, the rod E28 is pulled and the threaded sleeve '52 of the lower thread lock is rotated and unlocks the lower thread lock. During the unlocking of the lower thread look, as the machine comes to rest, the clamping shoe 26 of the upper thread lock which at this time is raised above roll 44 is raised still further above the roll. Thus both the upper and lower thread locks are opened when the machine comes to rest to allow thread to be pulled freely through them and thus enable the operator to withdraw the work from the machine before severing the threads.

The nature and scope of the invention having been indicated, and a construction embodying the several features of the invention having been specifically described, what is claimed is:

1. An outsole shoe sewing machine having, in combination, stitch forming devices including pull-off and stitch setting devices, a rear thread lock closed during the action of the stitch-setting devices, a front thread lock closed during the action of the pull-ofi" devices, and connections between the thread locks acting when actuated to open either look only while the other lock is closed.

2. An outsole shoe sewing machine having, in combination, stitch forming devices including pull-off and stitch setting devices, a rear thread lock closed during the action of the stitch-setting devices, a front thread lock closed during the action of the pull-off devices, and means operating against the resistance offered by either look after being closed for opening the other lock.

3. An outsole shoe sewing machine having, in combination, stitch forming devices including pull-off and stitch setting devices, a rear thread lock closed during the action of the stitch setting devices, a front thread lock closed during the action of the pull-off devices, lever and link connections between the looks, a spring acting on said connections to hold both locks closed, and a cam acting on said connections to open either lock against the resistance offered by the other lock.

4. An outsole shoe sewing machine having, in combination, stitch forming devices including pull-off and stitch setting devices, a rear thread lock closed during the action of the stitch setting devices, a front thread lock closed during the action of the pull-off devices, an actuating lever, connections between one end of the lever and the rear lock, connections between the other end of the lever and the front look, a spring acting upon one end of the lever to hold both locks closed, and a cam actuated lever upon which the actuating lever is pivotally mounted intermediate its ends.

5. An outsole shoe sewing machine having, in combination, stitch forming devices including pull-off and stitch setting devices, a rear thread lock closed during the action of the stitch setting devices, a front thread lock closed during the action of the pull-off devices, connections between the thread locks acting when actuated to open either lock only while the other lock is closed, and means operating on stopping the machine to open one of said locks while the other lock is open.

6. An outsole shoe sewing machine having, in combination, stitch forming devices including pull-off and stitch setting devices, a rear thread lock closed during the action of the stitch setting devices, a front thread lock closed during the action of the pull-off devices, lever and link connections between the looks, a spring acting on said connections to hold both locks closed, a cam acting on said connections to open either lock against the resistance offered by the other lock, and means acting on said connections on stopping the machine to open one of said locks while the other lock is open.

'7. A lockstitch sewing machine having, in combination, a curved hooked needle and a curved awl arranged always to lie in a common plane, a work-gripping device for feeding the work past the needle and awl, a thread pull-off device for pulling off from a supply of needle thread an amount sufficient for each stitch, a thread gripping device between the work and the pull-01f device arranged togrip the thread extending between the work and the pull-off device during the operation of the latter, a second thread gripping device between the said supply and the pull-off device arranged to grip the thread extending between the supply and the pull-off device after the operation of the latter, and connections between the two thread gripping devices arranged when actuated to open one of the devices only after the other has been closed upon the thread.

8. A lockstitch sewing machine having, in combination, a curved hooked needle and a curved awl arranged always to lie in a common plane, a workgripping device for feeding the work past the needle and awl, a thread pull-off device for pulling off from a supply of needle thread an amount sufficient for each stitch, a thread gripping device between the work and the thread pull-off device arranged to grip the thread extending between the work and the pull-off device during the operation of the latter, a second thread gripping device between the said supply and the pull-off device arranged to grip the thread extending between the supply and the pull-off device after the operation of the latter, one of which thread gripping devices comprises a roll over which the thread passes and a thread clamping shoe arranged to be moved to clamp the thread against the roll and the other of which devices comprises a pair of thread gripping plates arranged to be actuated to grip the thread between them.

9. A lockstitch sewing machine having, in combination, a curved hooked needle and a curved awl arranged always to lie in a common plane, a workgripping device, a take-up for controlling the needle thread, a looper and thread hook which cooperate to lay thread in the needle barb and an auxiliary tension device which comes into operation before the thread is laid in the needle barb to impart additional tension to the thread and retires out of operation after the thread has been laid in the needle barb.

10. A lockstitch sewing machine having, in combination, a curved hooked needle and a curved awl arranged always to lie in a common plane, a work-gripping device, a take-up for controlling the needle thread, a looper and thread hook which cooperate to lay thread in the needle barb, and. an auxiliary thread-gripping spring carried by the thread hook operating momentarily to press the thread against a cooperating member as the thread is laid in the needle barb.

11. An outsole shoe sewing machine having, in combination, stitch forming and setting devices including a pull-off, a rear thread lock closed during the action of the stitch-setting devices, a front thread lock closed during the action of the pulloif, and link connections between the looks, a spring acting on said connections to hold both locks closed, means acting on said connections to open either lock against the resistance offered by the other lock, and a second spring for ensuring that the rear thread lock will remain closed until the thread is clamped by the front thread lock.

12. A lockstitch sewing machine having, in combination, stitch forming devices including a curved hook needle, a curved awl, a looper, and a rotary take-up member, a continuously rotating shaft to which the take-up is secured, a thread lock, a pull-off for withdrawing thread from the lock, and a cam on the take-up shaft for actuating the thread lock.

13. A lockstitch sewing machine having, in combination, stitch forming devices including a curved hook needle, a curved awl, a looper and a rotary take-up, a continuously rotating shaft to which the take-up is secured, thread locks, a pull-off acting on the thread extending between the thread locks, and a cam on the take-up shaft for actuating the thread locks alternately in proper timed relation to the take-up motion.

14. A lockstitch sewing machine having, in combination, stitch forming devices including a curved hook needle, a curved awl, and a looper, needle thread measuring and locking means, a take-up for controlling the needle thread and an auxiliary tension device operating momentarily to press the thread against a cooperating member between the take-up and the looper as the thread is laid in the needle barb.

15. A lockstitch sewing machine having, in combination, stitch forming devices including a curved hook needle, a curved awl and a looper, a take-up for controlling the needle thread, an auxiliary friction tension device operating between the take-up and the looper as the looper lays the thread in the needle barb, and a connection between the tension device and one of the stitch-forming devices to release the thread therefrom after the looper acts.

16. An outsole sewing machine having, in combination, stitch forming devices including thread locking means, a pull-off and a take-up, a work support, a presser-foot, mechanisms for actuating the presser-foot to grip and release the work, and the pull-off to move in measuring 01f thread a distance proportional to the separation of the presser-foot from the work support while engaging the work, guide rolls of equal size, two of which are separately mounted and cooperate with one on the pull-off in such relation that at the start of the pulling off operation the distances between the nearest sides of the cooperating rolls and the pull-off roll are both approximately equal to the radii of the rolls.

17. An outsole sewing machine having, in combination, stitch-forming devices including a takeup, mechanisms for actuating the stitch-forming devices and a thread lock against which the stitches are set comprising a stem mounted for lengthwise movement, a block fixed to one end of the stem and a second block having a rounded rib rotatably supported in a fixed part of the machine to cooperate with the first block in gripping and releasing the thread when the first block is moved against it.

JOSEPH GOULDBOURN. THOMAS AUBREY KESTELL. 

